Cyclooxygenase-2: a new target for epithelial cancer treatments - Cyclooxygenases

Two isoforms: There are two isoforms of cyclooxygenase (COX) with similar s tructure and metabolic activity. COX-1 is a constitutional enzyme. COX-2 is an inductible form. Cyclooxygenase-1: COX-1 is present in most tissues, particularly in the kid ney, the digestive tract mucosa, platelets, brain, liver and spleen. Cyclooxygenase-2: COX-2 expression can be induced by an inflammatory proces s. Implicated in the development of certain cancers, COX-2 is expressed in numerous tumor cell lines and in most epithelial carcinomas. COX-2 favors t umor invasion and inhibits apoptosis. When it is absent tumor growth is slo wer or stopped. (C) 2001, Masson, Paris.